Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

9.1.8

424 views

Published on

Published in: Business, Technology
  • Login to see the comments

  • Be the first to like this

9.1.8

  1. 1. Power in = √3×VL×IL×cosø
  2. 2. Where: Power in (Pin) = Watts or kilowatts V = Supply voltage volts I = Stator Current in amperes ø = Power factor
  3. 3. Efficiency is a comparison between input and output power expressed as a percentage.
  4. 4. Example Calculation for Efficiency: A 40 kW 415 volt three phase induction motor requires a full load current of 70 amps per terminal at a power factor of 0.88. What is the motorʼs full load efficiency?
  5. 5. Answer: The motor has a power output of 40 kW the motor has an input of power determined by Pin = √3 x VL x IL x Cos ø
  6. 6. Pin = √3×415×70×.88 = 44.278 kW
  7. 7. Efficiency is Power out x 100 % Power in
  8. 8. Therefore efficiency is 40, 000 x 100 = 90.3% 44,278

×